$ git clone -n https://src.fedoraproject.org/rpms/rubygem-gstreamer.git /var/lib/mock/f42-build-865337-173025/root/chroot_tmpdir/scmroot/rubygem-gstreamer
Cloning into '/var/lib/mock/f42-build-865337-173025/root/chroot_tmpdir/scmroot/rubygem-gstreamer'...
$ git fetch origin ab876a3a09d4d601851a68e72372e028d2dfb505:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-gstreamer
 * [new ref]         ab876a3a09d4d601851a68e72372e028d2dfb505 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ab876a3 Rebuild for https://fedoraproject.org/wiki/Changes/Ruby_3.4